The present invention relates to bulldozers or the like having transversely extending blades and, more particularly, to a hinge connection between the dozer blade and pushbeams.
The blade of many earth-working vehicles is pivotally mounted forwardly of the front end of the main frame on pushbeams or push arms which extend rearwardly and flank the track frames. The pushbeams are pivotally connected to the track frames near the rear of the vehicle. The prior art pivotal connections between the blade and pushbeams increase the projection of the blade beyond the front of the dozer tracks which is undesirable.
It is conventional practice to provide clevis-type connections between the pushbeams and the back of the blade for permitting movement of the blade about a transverse horizontal axis. These pivotal connections typically prevent the blade from being mounted close to the tractor by requiring additional spacing between the blade and the vehicle. There has been a need for a hinge connection between the dozer blade and the pushbeams which reduces the overall machine length thereby improving machine stability and maneuverability.
The prior art pivotal connections have prevented other desirable features in connection with blade mounting and movement on the bulldozer. The clevis-type connections are typically located near the lower end of the blade and on the backside thereof. They include spaced-apart lugs which are welded or otherwise secured to the back of the blade. A yoke portion on the respective pushbeams is pivotally connected between the lugs by a pin to permit pivotal movement about a transverse horizontal axis by the blade on the pushbeams. These connections are somewhat loosely fitted, and they permit slight uncontrolled movement of the blade. For example, they yield to a limited extent when the blade is subjected to lateral loads thereby permitting the positional setting of the blade to change which is undesirable. Thus, there has been a need for a hinge connection that stabilizes the blade against uncontrolled movement.
Another problem associated with prior art hinge connections is that debris falls over the top of the blade during operation of the bulldozer and becomes trapped between the clevis-type pivotal connections and pushbeams. This can result in damage to the pivotal connections, blade or pushbeams during pivotal movement of the blade about a horizontal axis. There has been a need for a hinge connection that provides more open space between the tracks and the back of the blade to reduce the possibility of debris accumulation.
These disadvantages of present bulldozer blade hinge connections have resulted in the hinge connection in the present invention which reduces the overall projection of the blade beyond the front of the tracks, improves the control of the blade, and reduces the possibility of debris build-up.